I need to change the unit at my house, I have a central air unit that has gone on the blitz. I am getting some really high quotes to have it replaced. Do you think it's a good idea to try and change it myself.

Gotta get it done!!

also how do I get this done.

hvactech

03-14-2007 05:04 PM

It all depends, someone handy could do it, the tools needed to do the change over will cost you about $500, the unit depending on the size of your house will cost you between $1200 to $5000, there are plenty of good books out here that would guide you through the install.

Gotta get it done

03-15-2007 10:18 AM

Advice

Well I am pretty handy so that would not be a problem. What are the tools involved in the installation of these unit??

harleyrider

03-15-2007 12:23 PM

recovery machine
recovery tank
refridgerant scale
manifold set
torch set
hand tools way to many to mention
epa certifacation
tubing cutters
sand cloth
brazing rod
vacume pump
micron gauge
ect ect ect...........thats at least $2000 worth of tools...........still want to do it your self? Live close to Ohio? Ill come and put it in for you for less.......

Gotta get it done

03-15-2007 01:36 PM

Gotta get it done

lol naw, I live all the way in Florida but thanks though

harleyrider

03-15-2007 02:36 PM

The point I hoped to make was that its complicated, involved.....and NOT a DIY prodject in any stretch of the amgination. If you are able to some how buy a A/C (with out a EPA card your not supposed to be able to buy one) Your best bet is to have a Trained HVAC guy with the proper tools put it in for you.

the unit come with enough freon charge on it from the factory, keep the copper lines at less than 25 feet and you are good to go.The rest of the hand tool including tubing cutter you could buy from harbor freight tools for less than $60 for all. There isn’t much to it...in my opinion

hennyh

03-15-2007 05:37 PM

I just replaced my 4T AH and HP. It's not an "average" DIY project but if you're willing to invest the time and don't mind a challenge then go for it.

Quotes from contractors ranged from $8-12K. I completed my job for about $4k. (approx. $3k was equipment and supplies and about $1K was instruments, specialty tools and misc). I did a better job then most pros would have since I spent the time doing it right.

I spend over 100 hours in the planning and learning stages before I even started the project. The first step was to become EPA608 Universal certified. (to legally purchase and handle refrigerants).

There are tons of online suppliers for the equipment and you don't need to be licensed to buy equipment. Just be forewarned that you'll likely become your own warranty provider if there's a problem. The distributer you buy from will likely replace defective components but you'll be on the hook for diagnostics, labor and delays in shipping components back and forth. (don't count on local warrantee support).

HVAC is not easy and the "devil's in the details". You need to do it right whether you're a contractor or DIY'er. It can be rather unforgiving to hack installations and can be dangerous if you don't know how to work with high voltage circuits or refrigerants. You'll also likely face some challenges that you didn't plan for!! Don't forget that it's an entire system vs. individual components. That means condensor needs to match evaporator, evaporator needs to match air handler, air handler needs to match duct system, and duct system needs to match house. If one of those of out of whack it'll affect the entire performance of the system.

You're the only one that can make the decision. My motivation started out as cost savings but quickly changed to a passion to learn HVAC and do an installation that meets my high standards. It was a fun project.

Hope this helps.

P.S. Both of the other posters forgot about the Nitrogen tank and regulator. (For purging, leak test and brazing shield gas.) You definately need the Micron vacuum gauge. I'd also recommend a Halogen leak detector (get a used H-10 on Ebay) and a bottle of Miracle Bubbles ($.99).

There's no need for an expensive recovery machine/recovery cyclinder. You can get a cheap manual recovery machine like a Spooter II. Or you can hire out the decommissioning or do a pump down and take the old unit to a recycling center for refrigerant recovery.

the unit come with enough freon charge on it from the factory, keep the copper lines at less than 25 feet and you are good to go.The rest of the hand tool including tubing cutter you could buy from harbor freight tools for less than $60 for all. There isn’t much to it, a well trained monkey can do :thumbup:

I strongly disagree...that is incorrect

troubleseeker

03-15-2007 08:01 PM

Quote:

Originally Posted by Gotta get it done
(Post 36994)

I need to change the unit at my house, I have a central air unit that has gone on the blitz. I am getting some really high quotes to have it replaced. Do you think it's a good idea to try and change it myself.

Gotta get it done!!

also how do I get this done.

Sorry, changing an AC unit is not a DIY project. Are you changing the inside coil also or just the exterior compressor (condensor) unit? If your existing system is old, there is going to be a big difference in the efficiency of the new compressor to the old. Using the old inefficient inside coil, that is probably also caked up with dirt gunk, is not going to let the new compressor operate efficiently.